Jan Maria Michał Kowalski (25.12.1871 - 26.05.1942) was the first Minister Generalis (Minister General) of the order of the Mariavites. At the time of his selection, he was the most important person in this Christian movement. He was consecrated Bishop in 1909 by the Utrecht Union Old Catholic Archbishop Gerardus Gul. In 1919 the Mariavites officially changed its name to the Old Catholic Church of the Mariavites. Bishop Kowalski later called himself Archbishop. Bishop Kowalski died during World War II in the Dachau concentration camp. His successor was his wife, Bishopess Izabela Wiłucka. She was succeeded in 1946 by Bishop Józef Maria Rafael Wojciechowski. He died in April 2005 and was succeeded by Bishopess Beatrycze Szulgowicz.